Table 3.

Univariate Analysis of the Clinical Pathologic Factors Associated with Bilateral Paratracheal LNM in Papillary Thyroid Cancer

Variable	Number and Percentage of Patients with Bilateral Paratracheal LNM			χ2	P value
	Yes	No	M rate
Age
<55 years	22	89	19.8%	4.329	0.037
≥55 years	5	58	7.9%
Sex
Female	20	122	14.1%	1.209	0.272
Male	7	25	21.9%
Tumor size
≤10 mm	9	51	15.0%	0.019	0.891
>10 mm	18	96	15.8%
Capsule invasion
Yes	16	55	22.5%	4.506	0.034
No	11	92	10.7%
Extrathyroidal extension
Yes	8	22	26.67%	3.437	0.064
No	19	125	13.19%
Tumor location
Isthmus	22	55	28.6%	17.955	<0.001
Lobe	5	92	5.2%
Pathologic subtype
Classical	16	97	14.16%	0.453	0.501
Non-classical	11	50	18.03%
Hashimoto’s thyroiditis
Yes	7	44	13.73%	0.177	0.674
No	20	103	16.26%
BRAF gene mutation
Yes	25	102	19.7%	6.230	0.013
No	2	45	4.3%
TNM staging
I + II	20	111	15.3%	0.025	0.874
III + IV	7	36	16.3%
Pretracheal LNM
Yes	18	32	36.0%	22.454	<0.001
No	9	115	7.3%
Prelaryngeal LNM
Yes	6	24	20.00%	0.556	0.456
No	21	123	14.6%

Note: Significant values are shown in bold.

Abbreviation: LNM, lymph node metastasis.